Peerless Shower, Help identifying cartridge

Hello,

I have attached a picture to this post of a shower that is not working properly. When I turn the lever, water comes out from where the lever/cartridge is. I took the lever off and, as you can see in the picture, it looks like the plastic of the cartridge is broken.

I am assuming I can pull this cartridge out and replace it with a working one. Am I correct?

If I am, can you guys help identify what the replacement is? The cover around this lever has "Delta" written on it. It looks like a Delta Scald Guard to me but... I could be wrong.

Also, how do I uninstall this old cartridge? I am afraid to just start turning and prying on things.

Thanks for any help,

Travis

 

Attached.

 

The retainer nut will screw off counterclockwise. The new RP70538 cartridge will look a bit different. It was redesigned in 2015. Be sure to replace the RP73625 check valve as well.

https://media.peerlessfaucet.com/PartsDiagram/PPD-B-PTR188700-UN.pdf

 

Thanks a lot!